A key fob is an electronic transmitter for signaling a receiver on a vehicle. Typically, key fobs include a housing receiving the transmitter. The transmitter is capable of transmitting multiple signals for actuating multiple vehicle devices. One type of key fob provides the switches with domes protruding through the housing. Each of the domes is depressable for completing a circuit and initiating transmission of a different signal from the other domes. Each different signal actuates a different device on the vehicle such as, for example a door lock/unlock, a trunk unlatch, a panic alarm, and the like. Key fobs are carried with a key chain along with an ignition key. As more and more functions are provided on the key fob, the number of required switches increases. However, this also increases the necessary size of the key fob, which is undesirable.
Thus, it would be desirable to reduce the size of the key fob, and yet retain the functional attributes available with current designs. Because vehicles have ever increasing numbers of electronic devices, it is desirable to add functions to a key fob and not remove functions. Therefore, reducing the size of the key fob housing by simply eliminating remote control functions is not desirable. Thus, it would be preferable to reduce the area required for the switches controlling each of these function.
The present invention discloses a switch assembly that provides two elements to control two functions. A key fob for signaling a receiver on a vehicle includes a housing having a transmitter. The transmitter is capable of transmitting multiple signals for actuating multiple vehicle devices. Switches are provided in the housing by a plurality of domes, which protrude through the housing. Each of the domes is depressable for initiating transmission of a different signal from the other domes. For example, one signal causes a vehicle door to unlock and another signal causes the door to lock. As is well known in this art, such key fobs send a radio frequency signal through the air without any hardwire connection.
At least one of the domes includes two elements placed directly adjacent each other. Each of the elements is independently depressable for initiating transmission of a different signal from the other element. Therefore, it is possible for a single dome to transmit signals to both unlock and lock the vehicle door. The first element protrudes through the housing to a different height than the second element. This facilitates actuating only one of the elements without actuating the other.
Including the two functional elements in the single dome facilitates size reduction of the housing, and therefore of the key fob. The inventive domes capable of initiating transmission of two signals facilitate including more remotely operable vehicle devices on the vehicle.